Wizcrafts

I have a few observations based on your comments Danno. First, the thread lying flat on the bottom can be caused by the following misadjustments: Bobbin case spring way too tight Top thread spring way too loose Top thread too springy, causing it to flip out of the center area of the tension disks (no top tension) Needle too small to pull knots up into leather Normally, the bobbin thread tension spring is set for a light, even pressure when you pull on the bobbin thread. If it is very hard to pull the thread that emits under the tension spring, something is binding as the thread leaves the bobbin. It could be a burr on the spring, or maybe the thread has unwound around the bobbin inside the case, or you left too long of a starting stub after cutting it off with your thread snippers. Also, if the bobbin case has an anti-backlash spring inside it and the bobbins are just a little on the wide side, the case and anti-backlash spring could jam the bobbin against the shuttle face, adding a lot more tension than you expect to have. Always prove the bobbin tension after pulling the thread up through the feed dog hole. Issue #2 can be fixed by adding more spring tension to the top disks. Screw in the adjuster nut to add more pressure from the beehive shaped spring. Improvements are usually noticed right away, unless issue #3 exists. Issue number 3 is trickier. This happened to me last year, as I was sewing. It is a known secret among professional leather sewers that a lot of times a spool of black thread will unwind like a coil spring. These windings tend to form twists and even knots along the path to the needle. One day, as I was happily sewing long strap on my walking foot machine, the top thread started bunching up under the leather and motion ground to a halt. There was zero top tension! When I followed the thread back from the needle to the top tensioner, I found that the thread was literally sitting on top of the disks, rather than down inside them. It was black #138 bonded nylon thread and it unwound like a clock spring. First, I tried looping the thread around a post on top of the machine, which added back tension, which helped pull the thread down into the business area of the disks. But, due to its springiness the thread formed another loop around the post and jammed the machine to a halt, filigreeing the leather. When this kind of trouble happens and you have no other suitable thread to change out to, you find unusual solutions. My unusual solution, which I am still using, is to feed the top thread under the little 1/16" diameter steel pin that keeps the top tension disks in alignment. The disks have a little semi-round cut-out that flits over the little spring-pin. My thread feeds straight through the top post, winds around the three hole guide over the right side of the tension disk assembly, goes under the little spring-pin, then a sharp turn up to the left and around the tension disks, then down to the check spring assembly and on to the take-up and feed down guides. With this configuration my top thread has never again twisted itself out of the top tension disks. The sharp turn up from the pin adds more tension, so I no longer feed through two holes on the top post. It simply isn't required any more. I explained in the last paragraph that some thread is more springy than other threads. This is especially true of bonded black nylon, which is often redyed from a dark blue to black. I now keep different brands and batches of black thread on hand, purchased at different times. Some is springy, some is less so, some not at all. Bonded polyester tends to be much softer and less springy in all colors I have on hand. As for the needle sizes, #69 (T70) thread is usually sewn with a #16 or #18 needle and usually produces a great stitch in thin materials, like Naugahyde and garment leather and motorcycle patches on vests. However, if the tensions are decent, top and bottom (no jammed threads), but the knots lie under the leather, and the machine is properly threaded and the top thread has not lifted out of the top disks, increase by one needle size for a larger hole. If necessary, you can even try sewing with a #20 needle. Matching your reverse stitches can also be fine tuned by changing the timing of the alternating presser feet on the back of the machine head. In my photo below, the big six sided bolt locks down the timing of the feet, while the nut-secured sliding piece, that moves in the curved slot, controls the amount of lift the raised feet have. By loosening the big bolt, and rotating the shaft connected to it, you can adjust the moment when the inside foot makes contact with the feed dog to happen just after the tip of the needle passes the top and begins to enter the hole. Do this while the needle and inside foot are on the down stroke, without material under the foot. You will probably have to adjust it a few times before you zero in the stitch length to match in forward and reverse.

I used to have two old Singer post machines, both equipped with roller feet. I used them to make leather caps and cowboy hats, as well as to sew moccasins. Most of the newer post machines can sew with up to #138 thread, whereas my old ones barely handled #92. Cylinder arm machines can be had in light, medium and heavy duty constructs. A shoe patcher (Singer model 29 and 29k) is what I would call a light duty cylinder arm machine, capable of maybe sewing no more than 1/4 " of leather with #69 or #92 thread. A Consew 227 type machine, such as the Cowboy clone that I pictured in my previous reply, can sew all day with #138 thread, up to 3/8" of leather. A big Cowboy, Cobra, or Techsew 441 clone cylinder arm machine can sew up to 7/8", with #346 thread, and even #415, using huge needles resembling porch finishing nails in diameter.

Yes, a needle feed machine, slowed way down, with a slotted Teflon or roller equipped presser foot will serve well for most flat work and linings. Just make sure you buy feet with a long slot between the toes. Some straight stitch feet just have a fixed position hole, which would be a disaster for you. Also, most of those machines are meant to sew shirts and have small needle holes and dog teeth. If that machine doesn't do what you want, or runs too fast, sell it and buy a common, manually oiled straight stitch with a fixed position needle.

I use different sewing machines for different tasks and materials. I have found that my large Cowboy stitcher does not do as well sewing with thin thread and with heavy thread. I have to dink around more than it is worth to change over from sewing with #277 to #92. Tis better to keep a medium duty walking foot machine for middle weight jobs, small thread and small needles. Also, long needles bend more easily than short ones. So, I use a harness stitcher for holsters, a walking foot machine for thin flat items and a shoe patcher for sewing in different directions, or on top of pockets, or inside sleeves and legs.

I keep a straight stitch machine, with a servo motor and a big variety of presser feet, for such projects. A few nights ago I used my Singer 31-15 (a straight stitch, bottom feed only machine) to sew a lining that had separated, inside a pair of leather pants. I then sewed the fixed lining between two layers of garment leather. The machine was threaded with #69 bonded nylon and I had a flat, roller foot equipped attached to the presser bar. The little rollers allowed both the satin lining and garment leather to feed without any binding whatsoever. The machine is equipped with a medium tooth feed dog and a round throat plate hole big enough to clear a #20 needle (I only used a #18 needle for this job). My National walking foot machine might have eaten the lining, because of the way the feet work and the largish oval hole in the moving feed dog.

This is a cylinder arm machine: This is a post machine:

Palermo; If you do buy a 441 type machine with the intention of sewing soft or thin leather, also get the accessory flat slotted throat plate and some packs of thinner needles (e.g. #18, 19, 20). You'll need to remove the feed dog and standard plate to use this plate. It has a long, narrow slot for the needle to move the work. The width of the slot is much smaller than the hole in the feed dog. That large hole causes skipped stitches and stitch length inconsistencies in soft garment leather and other soft materials.

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Bob is also right. If there are grooves worn into the tension disks, bobbin spring, guides, or take-up lever, the thread will tend to fray. How fast do you sew?

That is not normal for premium bonded thread. It may be a bad batch or poorly bonded (it happens). Try using a different brand (or batch number) of thread. Alternately, try running the thread through silicon lube in a lube pot, or magnetic lube jar. You might even try soaking the spools in a quart or gallon of silicon lube.

Tony; You can run a stitch marking wheel over the last machine stitches, up to where the hand sewing ends. This should keep the spacing constant, depending on your stitch length used on the machine. Most overstitch wheels don't exceed 5 to the inch, but our machines can easily pass that length. If an overstitch wheel doesn't work for you, use sharp point dividers set the your stitch spacing.

A typical Juki 441 or clone is not usually set up as a leather sewing machine. They contain parts and are timed to sew tents, tarps, buffing wheels, tow ropes, horse blankets, padded car seats, etc. As such, these machines are equipped to sew at about 10 to 15 stitches per second. Here are some of the changes that must be made to make a Juki 441 or clone into a dedicated leather stitcher. Change feed dog to custom made smooth type (original has aggressive teeth) Change big, wide, tooth-bottomed blanket presser feet to narrow, smooth bottomed harness feet, plus include a left and a right single toe outside foot. In the case of Cowboy 441 clones, change feet, feed dog and throat plate to stainless steel parts. Adjust reverse lever to sew into same holes. Increase lift to at least 1 inch (factory lift is 3/4 inch), allowing sewing to 7/8 inch of leather. Change motor to powerful, slow speed capable servo, with very small motor pulley, which feeds a speed reducer wheel, which drives the machine at about 8 or 9 to one speed reduction/torque multiplication. This allows you to sew at less than one stitch per 2 seconds, up to about 7 per second (depending on your motor). Adjust timing and placement of hook for best results when sewing leather, forward and reverse. Non-leather projects do not usually deflect the needle sideways as much as leather does. Optional installation of a wax/lube pot. This can be filled with liquid silicon thread lube, sewing machine oil, or (Ceroxylon) liquid wax. The lift and timing of the alternating feet may be altered for best timing with the motion of the feed dog, needle and inside foot. The pressure spring may be replaced with a heavier duty part, capable of holding down 7/8 inch of leather. Accessory throat plates may be included, or sold as accessories. These include a raised holster plate, a raised, rounded top stirrup plate, and a semi-flat, narrow-slotted plate that is used without the feed dog. Using the slotted plate without the feed dog can produce a bottom stitch line that comes close to the appearance of a needle and awl machine. Every nut and bolt gets inspected and tightened down, which doesn't always happen at the factory. ;-( Paint or casting mishaps are corrected before the machines are sold. Machines are tested with real leather, stacked to about 7/8 inch. The machine must sew to that thickness if it is advertised as capable of doing so. These are some of the things that our dealers do to each 441 clone they have for sale. It takes upward of 4 to 6 hours per machine to convert them into proper leather stitchers, assemble them onto pedestal tables with speed reducers, and sew them off. If you were to buy a no-name 441 clone, you would have to purchase all these parts from our dealers, who have them made to order, then upgrade and readjust the machine yourself.

I now get Family Sew motors from Toledo Industrial Sewing Machines. They have a rotary speed control switch on the front and lots of power. Your Juki is a light duty dual feed machine, with a fixed needle position. It was built to sew cloth garments, not leather. Thread-wise, you'll be pushing it with black #138 bonded nylon. You'll be better off buying the more expensive, but typically softer bonded polyester thread. Sewing with #138 thread, top and bottom, requires either a #22 or #23 leather point needle. Schmetz are best, if you can get them with an S point favored by most of ussens.

Those are sold as zipper feet. Get smooth bottom feet or they'll leave tooth marks in the top grain. If you have trouble finding smooth bottom single toe outer feet, buy two more standard (double toe) walking foot sets and grind off the left toe on one and the right toe on the other. Afterward, get a swing-away edge guide.

By the time you buy a servo motor and new belt and pay shipping, you'll be well over $800. This, for a 20 year old first of its kind machine. For about $500 more, you can get a brand new series 5 Consew, with a warranty and new servo, already set up and ready to sew. Just sayin'.

Your hand sewing thread is about the equivalent of #207 (3 cord) or #277 (4 cord) bonded (nylon or polyester) machine thread. Bonded Polyester is a tad softer than the same size of nylon, forming knots more easily, and is UV resistant. The vast majority of industrial sewing machines cannot handle #277 thread at all. You need to look into an Adler 205-374, or clone, or a (Juki) 441 clone. An actual Juki 441 is not shipped equipped to sew leather; it needs a lot of modifications. The 441 clones, like Cowboy, Cobra and Techsew, as sold by our dealers, have been modified for leather work. All of our advertising dealers can ship a machine to you by ocean freighter. As for machine sewing with linen thread, it is a crap shoot. Pre-waxed thread gums up the guides and tension disks and clogs the needle. Post-waxed (with liquid wax) 3 or 4 cord linen thread tends to break after so many stitches. Mind you, I have not tried using 5 or 6 cord Irish linen in my Cowboy CB4500, as I have none at this time. But, the 3 and 4 cord threads have problems after running through the liquid in the wax pot. The machine you choose must have large needle capacity. You will be using needles ranging in size from metric 180 and up. I usually sew with #277 thread and it requires a #25 (200) needle. This is the standard factory needle on an Adler 205. It would be the minimum size needed to sew with 4 cord (pre or post waxed) linen. However, thick bonded threads need a certain amount of thickness of leather to form a properly positioned lockstitch. Anything thinner than about 9-10 ounces will give the machine trouble placing the knots inside the leather. We usually use thinner thread, like #138 or #207, on thin leather, like 6 to 8 ounces. The difference between hand sewing with two needles and machine sewing is that the hand thread forms daisy loops - over and under the leather. There are no knots between the layers. Most sewing machines form a lockstitch, with a knot formed inside the material. The top thread gets pulled around a bobbin, capturing the bobbin thread and pulling it up, forming a wrap around knot. The thickness and toughness/softness of the thread affects these knots. Black bonded thread tends to be stiffer from multiple doses of black dye, so it needs more tension and more thickness to hide the lockstitch knots. Bottom line is, you'll always be able to use thicker linen thread when you hand sew with two needles (daisy loops), than the bonded threads required by industrial sewing machines (lock stitches). Linen (glazed or waxed) bends much easier than bonded nylon, which bends a little harder than bonded polyester. Most sewing machines don't like waxed thread, unless you are very careful and clean the guides, disks and needle after each use. Note, there are some machines that were made to use waxed linen thread. They are horribly expensive, very heavy and usually ancient (but rebuilt). Brands that I have used are Union Lockstitch and Campbell-Randall. Also, some shoe sole stitchers can sew around the perimeter of leather goods, using waxed linen thread. Prices A new Adler 205 might cost you several years income. You can buy a 441 clone from the USA and have it shipped to you for half the cost, landed.

The foot lift can be modified by the owner. However, foot lift is tied into top thread disk release. If your machine has adjuster nuts over/under the presser bar, fastening to the lift plate, adjust them to allow the foot to lift higher before disengaging the disks. Once you reach the height where the hand lift lever engages, there is no more lift to be had. I suspect that most tweaked Singer patchers will max out at just under 3/8 inch of lift, allowing you to sew about 5/16 inch. The machine needs clearance to let the foot pull the work, then return to its starting position. If you need higher lift and sewing capacity, buy an Adler 30-70, or a newer Claes patcher. That Adler actually sews 3/8 inch and the Claes manages almost 1/2 inch.

You'll get better results if you run one size smaller thread in the bobbin than on top, with that machine, if you go above size 207. If you limit the size of the top thread to #277, and use #207 in the bobbin, it shouldn't give you any trouble. You will need leather point needles, in sizes 22, 23, 24 and 25. This covers a range of thread from 138 through 277. Note, the feed system is not a real walking foot. It has a spring loaded top foot that simply follows the work backwards, until the feed dog drops. At that point, it snaps forward for the next stitch. You should read this topic about the Singer 132k6 for a better understanding of its capabilities and limitations.

Juki LU-1508NH

#138 thread, top and bottom = #22 or #23 leather point needle (for leather). If a #22 leaves knots visible on the bottom, move up to #23. Increasing the size of the thread usually requires either loosening the bobbin tension, or increasing the top tension. But, moving up to a larger needle can offset this. If the larger needle leaves too large of a hole, the knots will be able to slip up and down. If that happens, move down to the smallest needle that freely passes the top thread, then increase the top tension to bring the knots up Depending on the density of the leather, increasing your needle size may also require more spring pressure adjustment on the presser feet, to prevent the leather from lifting with the ascending needle and thread.

You can't beat a straight top thread path and minimum hard turns for smooth sewing! I started using pre-lubricated thread some months ago and it more or less does away with the need for silicon in the lube pot. However, I still run some other threads through the lube if their bondings aren't up to snuff, or they are too dry. I do run all brands of thread through the lube if the needle is running smoking hot, which happens at about 8 to 10 stitches per second, sewing medium temper leather (production runs). Once turn around the bottom post is okay, as long as you aren't using it to add much more top tension. One turn also makes it easier to extract the thread when you fully lift the presser feet with the floor pedal. Note, this means that the top tension disks do most of the work on the top thread.

Red Cent; Please check the spool of thread for flip-overs, twists, or possibly the thread winding under other windings as it feeds off the spool.. Follow it through the top guide posts. Make sure you feed it through the little loop in front of the top tensioner. BTW: that steel loop should sit as low as possible in relation to the axis of the tension disks. The greater the angle, the better the feeding around the disk axle. I have experienced too much check spring (the spring wrapped around the bottom disks that you must feed through on the way up to the take-up lever) tension over-riding the top tension, after reducing the top tension setting to very light. There is a nut, or a set screw on the opposite side of the housing for the bottom disk axle. Loosen that nut or set screw and turn the split shaft whichever way reduces the spring pressure, while still allowing it to move up and down, then lock it back down. Last, open the bobbin case and blow out any thread fragments. Ditto for the shuttle and shuttle race.

Eric; The Janome New Home came to me with the Pfaff serger and it was almost seized. After freeing it up and getting it back into order it sews like a champ. It even does a couple of small alphabets, like for names on shirt cuffs. The patterns can be mirrored, stretched or widened, making for some interesting layouts. Of course, the machine cannot sew over 3/16 inch without great difficulty, nor use anything stronger than B69, but it wasn't meant to.

Right now I have the following industrial machines in use. Cowboy CB4500 heavy leather stitcher (w/servo) National 300N walking foot machine (w/servo) Singer 139 long body, walking foot machine (w/servo) Singer 29k172 long arm, big bobbin patcher (foot treadle) Singer 31-15 straight stitch machine (w/servo) Fortuna bell knife skiver (clutch motor) Pfaff 4 thread, two needle portable serger Additionally, I own the following, fully functional domestic sewing machines, which I sometimes use. 1921 Singer 66 Red Eye mounted onto a table with knee lever speed controller 1942 Kenmore Rotary Deluxe, mounted on a table with a knee lever controller 1970s Kenmore 158.142 cam driven multi-function sewing machine, Does 3/4 inch embroidered letters. 1980s Janome New Home electronic sewing machines, for pattern stitching and various zig-zags. Mint, 1953 Singer 15-91, with rebuilt motor. Near mint, 1929 Singer 99, with a removable knee lever speed controller, in a bentwood case.

Try straightening out the top thread path. If you have it wrapped around a top post, change to inline feed through instead. Make sure that the starting piece of bobbin thread is cut off flush with the side of the bobbin. If a little nib is protruding, it might interfere with the feeding of the bobbin. It is also a good idea to test the bobbin thread after loading it. Pull a couple of feet and make sure it pulls evenly, without sudden lumpiness. Dip the bobbin thread in your lube and see if it helps. You should be able to pull the top thread through all the guides and tensioners, with the presser feet fully lifted. If the thread gives sudden resistance, find out where it is twisting, or binding. Black thread is the worst offender. Clean all guides along the top thread path.